Chinese Journal of Magnetic Resonance ›› 2010, Vol. 27 ›› Issue (2): 141-149.

• Articles •     Next Articles

An In situ High-Pressure MAS NMR Study of the Adsorption and  Hydrogenation Processes of CO

 XU Shu-Tao1,2, ZHANG Wei-Ping1, LAN Xi-Jie1, HAN Xiu-Wen1, BAO Xin-He1   

  1. 1. State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China;
    2. Graduate School of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2009-12-21 Revised:2010-01-11 Online:2010-06-05 Published:2010-06-05
  • Supported by:

    国家重点基础研究发展计划(“973”计划)资助项目(2009CB623507),BP Detal 项目.

Abstract:

The adsorption and hydrogenation processes of CO on Rh-based catalyst were studied by in situ high-pressure (HP) MAS NMR techniques under batch-like conditions. 29Si MAS NMR spectra showed that the silanol concentrations of the support Silicate-1 were reduced after impregnation of metal species. After introduction of 13CO/H2 below 200 ℃, only the average exchanged signal of CO between gaseous CO, linearly adsorbed CO and dicarbonyl adsorbed CO was observed on Rh/Silicate-1; while the titled adsorbed CO appeared on Rh-Mn/Silicate-1 or Rh-Mn-Li/Silicate-1. So, the addition of Mn or MnLi could enhance the CO adsorption. Under batchlike condition, high-pressure 13C MAS NMR showed that the CO/H2 reactants could only be converted to CO2 and CH4 on Rh/Silicate-1, while only CO2 appeared on Rh-Mn-Li/Silicate-1 at relatively lower temperatures. Meanwhile, 1H MAS NMR showed the obvious decrease of silanol groups after reaction that indicated CO could react with silanol groups to produce CO2.

Key words: NMR, In situ high-pressure MAS NMR, CO adsorption, CO hydrogenation, Rh-based catalyst

CLC Number: